1. Field of Invention
The present invention relates to fins for diving and more particularly to such a fin having a stretchable foot pocket so as to fit different individuals with various foot sizes.
2. Related Art
A conventional fin comprises a foot pocket for covering the human foot, and a blade extended forward from the foot pocket. A diver may put his or her feet in the foot pockets. In use, the diver may exert a force to vibrate the blades for propelling forward.
Conventionally, the foot pocket of a fin can be classified as either a pocket type (see FIG. 1) or a well type without an outside counter (see FIG. 2). For well type foot pocket, a strap A is provided around the heel and a snapping type fastener B is provided at a rear portion of the foot pocket for fastening the foot in the foot pocket by securing to the strap A.
One advantage of a fin having a pocket type foot pocket is that a person can easily find a fit fin to put his or her foot in the foot pocket. However, its disadvantage is that a number of fins with different sizes are required to be commercially available such that different individuals with various foot sizes may have a chance to select a pair of fit fins. It is often that a person wearing fins may feel discomfort if the foot pockets are too tight or too loose, resulting in an increased difficulty of moving.
One advantage of a fin having a well type foot pocket is that it is adapted to fit different individuals with various foot sizes. However, its disadvantage is that the fastening of the foot by the strap and fastener may become loose after a short period of time. Thus, the wearer may feel discomfort. Further, it may hook a foreign object, resulting in an increased difficulty of moving.
Typically, commercially available fins are formed of plastic material and have limited flexibility and resilience. Thus, continuing improvements in the exploitation of a fin having a stretchable foot pocket are constantly being sought.